Just How Can a Computer Do Magic? !
by Quatermass
Summary: ("Is Your Great-Aunt an AI!" sequel) GLaDOS has learned how to do magic, and is going to be teaching at Hogwarts. And it's just as well, for a plot is afoot to cause trouble at Hogwarts. Can a genius, if insane, computer and her great-nephew Harry stop things from spiralling out of control? Or will the beast of the Chamber of Secrets thwart even GLaDOS and Harry?
1. Foreword

**FOREWORD**

Sorry about the wait, but at long last, we're embarking on the long-awaited sequel to one of my most popular works, _Is Your Great-Aunt an AI?!_ To give you an idea of how popular it is, as of the time of writing, it ranks fourth on the amount of views of my fics overall (and second only to _Haemophilia_ for my Harry Potter crossovers), ranks second overall (and first amongst my Harry Potter crossovers) for C2s, and is, to date, my only fic outside the Cetra Heritage Saga to be recommended on TV Tropes.

I've dilly-dallied for long enough in bringing the sequel out, though. And here it is. Hope you enjoy.

Anyway, time for my disclaimers. Firstly, as with all my fanfics, there will be heavy annotations.

Secondly, there will be spoilers for both _Portal_ and the Harry Potter series. You have been warned, don't come crying to me.

Finally, the following is a fan-written work. _Portal_ and Harry Potter are the properties of their respective owners. Please support the official release. Otherwise, Wheatley will do something stupid that you'll both regret…


	2. Chapter 1: Why Would a House Elf Steal

**CHAPTER 1:**

 **WHY WOULD A HOUSE ELF STEAL MY LETTERS?**

 _Harry didn't understand what was going on. His Aunt (well, great-aunt) Caroline had disappeared a few weeks ago, leaving him in the care of a young woman who couldn't talk, save for using an electrolarynx. Big sis Chell was nice and all, but Harry missed Caroline._

 _He had been told that she had passed on, that she was dead, but there was some instinct screaming within Harry that they were lying. Harry didn't trust any of these adults, or at least few of them. They followed the orders of a dead madman, a madman that Harry only barely remembered. A jolly madman…but a dangerous one. His aunt liked the madman…but she had been cursing him in the last few days before she disappeared. She had been crying too. The night before she vanished, she had told Harry, tearfully, that she would always love him._

 _And then, one of the scientists had come and asked Chell to bring Harry to a big room, where a strange structure hung from the ceiling. For some odd reason, it seemed almost like a giant metal woman, trussed up and hung from the top of the chamber. Distantly, he heard Barney the security guard ask, "Why did you bring a kid in here?"_

 _"We've tried everything to calm her down, including those damn Cores. Maybe this might help. She was attached to him, remember?"_

 _"Yeah, she was his great-aunt. And you took her from him, you bastard."_

 _"Keep your voice down, moron!"_

 _Those words hadn't registered with Harry at the time. It was only later, when he looked back on the memory, that he realised what they had meant. However, the man who had brought him and Chell indicated the massive structure. "Isn't she beautiful? The Genetic Lifeform and Disk-Operating System. The world's true artificial intelligence."_

 _Harry was better read than most kids his age: it came from being brought up in Aperture Science. "An AI?"_

 _"Yep. So, let's switch her on!"_

 _Harry felt the hand on his shoulder, Chell's hand, tighten, in support and in tension. The massive structure about them shuddered, shivered, even seemed to convulse slightly. A whine that gently built up in pitch permeated the air. Then, the structure unfolded, and what could have been a head with a single, yellow eye peered at the gathered scientists_. "Initialization of Genetic Lifeform and Disk-Operating System complete," _the structure spoke in an eerie, lilting, electronic tone that sounded horribly, horribly familiar to Harry._

 _"GLaDOS?" the scientist who had made those comments to Barney asked. "How are you this morning?"_

 _There was a pause, before the voice spoke again_. "How curious, how simple, asinine questions have complicated answers."

 _As the scientist blinked, wondering whether he had been insulted (he had been), Harry had a flash of recognition. That voice…it couldn't be. "Auntie?" he asked, in a quiet, lost voice._

 _GLaDOS froze, before the massive body turned to face Harry, the baleful yellow eye narrowing, Harry recoiling like a rabbit in the headlights. The head of the structure tilted slightly, almost quizzically._

 _Distantly, Harry heard Barney say to the scientist, "I'll use technical terms to describe this situation, Doc: you done goofed."_

"Who…are you?" _That's what GLaDOS said, her lilting voice having a strangely plaintive element to it_. "Who…are you?" _Suddenly, she shrieked, doing a good imitation of a Dalek_ , "ANSWER!"

 _Harry recoiled from the scream, and Chell made to bustle him away, only for part of the floor to become a wall, obstructing their way. She fumbled around in her jacket, and fished out her electrolarynx, and snarled, in her buzzing monotone that nonetheless conveyed her anger at the situation_ , "You're frightening him!"

 _"I'M frightening HIM?!" GLaDOS retorted. "HE'S frightening ME! WHO IS HE?"_

 _"Shut her down!" yelled the scientist._

 _"No! She's Great-Aunt Caroline!" Harry yelled. "What did you do to her?!"_

 _"She's not Caroline Evans," the scientist snapped. "She's the Genetic Lifeform and Disk-Operating System."_

 _"I know that voice, that's Great-Aunt Caroline!" Harry yelled, struggling to free himself from Chell's grasp._

"No…no…no…I AM GLADOS! I AM _AM_ **_AM_** AM _GLAD_ TO BE HERE. **_GLAD_** TO BE MAKING SCIENCE."

 _"Sir, the systems, they're being taken over! GLaDOS is taking over Aperture Science!" someone yelled, understandably panicked._

"Indeed I am," _GLaDOS purred, her voice far more feminine and sultry. Her yellow eye turned into a demonic, diabolical red. And then, it became a masculine, if sibilant, voice, cold and high_. "Foolish Muggles. I have become immortal. And soon, I will be rid of Harry Potter…"

 _Pipes poked in through holes in the walls and ceiling. Sickly-looking green gas hissed in. Almost instantly, Harry began choking, as he heard the high, cold laugh from the supercomputer that was once his great-aunt_ …

* * *

It's a fallacy that people who have nightmares sit bolt upright in a panic, at least most of the time. But it can still happen, and Harry Potter, a few days short of his twelfth birthday, did so, screaming loudly, before his panic died down slightly. The room, whose systems were keyed to tell when he was awake, gently lit up. A few seconds later, the distinctive lilt of his great-aunt's voice emanated from the speakers. " _It is now 5:34 AM Eastern Time on the 27_ _th_ _of July, 2002._ " Then, rather more softly, GLaDOS' voice said, " _Harry…I heard you screaming. And as much as I love to test the decibel and hertz range of human voices under various stimuli including stress and fear, I must admit to concern._ "

"A nightmare," Harry said. "Thank whatever deity exists…"

" _You're welcome._ "

Harry scowled half-heartedly at GLaDOS' habitual display of hubris. "It was about that day. When you woke up, and Chell and I were there, and you panicked, and it all went south…except it was worse this time," he confessed. "You broke out the neurotoxin early…and then you started speaking like Voldemort."

GLaDOS, for a time, was silent. Then, she said, " _While I have many treatments at my disposal for nightmares, I believe a hug would be one you appreciate most. Would you like one?_ "

Harry nodded. Then, suddenly, with a loud _crack!_ , GLaDOS appeared in the room, or rather, her proxy gynoid. Slender, buxom, dressed in a figure-hugging skinsuit, with short silver hair, a beautiful if stern face, and golden eyes with black sclera, this was the body GLaDOS used whenever she wanted to physically interact with humans.

The gynoid gently knelt down next to Harry's bed, and hugged him, the robotic body surprisingly soft to his touch. As he returned the embrace, she said, her voice now less lilting and more human-like, " _You remember how the day truly went. You saved me that day, Harry. You did more for me than any of those scientists with more years of experience. They sliced my skull opened, and diced my brain as they uploaded it. You gave my soul back to me, twisted out of shape by their science though it was. I am both more and less than Caroline Evans now. But I will always be your great-aunt, Harry._ "

Harry nodded. It was rare that GLaDOS was so candid, so _human_ , like she was being now. Usually, she had a dark sense of humour, a tendency to pile on the hubris with a trowel, and a very loose sense of morality and workplace health and safety. But there was someone who loved Harry Potter deep inside her, and indeed, the rest of the loose little family that had sprung up around them both. Like Chell, daughter of a scientist, and now Harry's big sister and fellow test subject. Or Rattmann, a schizophrenic whose relationship with GLaDOS varied between paranoid fear and bemused collaboration. Or Wheatley, the Personality Core who was well-meaning but rather stupid. And there was Atlas and P-Body, a pair of testing droids.

And over the past year, they had been joined by more people. The first was Doctor Gordon Freeman, formerly of Aperture's rivals, Black Mesa, made to take the fall for sabotage, albeit necessary sabotage to prevent an invasion from another world. Freeman, while paranoid, egotistical, and an abuser of painkillers, was a decent enough guy. Harry had grown to like him, and vice versa.

The second and third additions to the family were, in a way, part of Harry's family from his birth, but circumstances had prevented them from being there for him. For Sirius Black, it was being framed for the murders of his parents and the real traitor to the Potter family. For Remus Lupin, it was the fact that he was a werewolf, and thus despised by much of magical society.

The latest two additions were somewhat stranger, even by Aperture Science standards. They were both ghosts, spirits of a sort, that Harry had captured during his first year at Hogwarts. One was a ghost by the name of Myrtle Warren, better known to students as Moaning Myrtle. Harry had asked her if she wanted to be captured, and she agreed, rather more swiftly than he had thought, simply because she was bored of haunting the same castle. Thanks to GLaDOS' experiments, she now had a gynoid body of her own. Wheatley, after some insisting, got his own android body, and the two had been dating.

The last addition, however, was not a pleasant one. In fact, he was Harry's self-appointed nemesis, Lord Voldemort. Harry had captured the twisted man's spirit in a split-second decision that he was surprised had worked. Said spirit had been possessing a teacher at the time, who didn't survive, and despite Quirrell being a willing helper of Voldemort, Harry still suffered occasional nightmares of that incident.

GLaDOS had transferred Voldemort's spirit into a Personality Core, plugged up the access ports (in the unlikely event that Wheatley got persuaded by Voldemort to hook him up to any computer system), and wired it into a potato battery. Aperture Science boasted that all equipment would be functional at 1.1 Volts, and with Personality Cores at least, stripped of anything superfluous, this was true. Though if Voldemort ranted, raved, or stressed out too much, his Core would short out and shut down temporarily. Harry sometimes went down there, usually to taunt his nemesis, though he sometimes just sat there and glared at Voldemort.

Harry then realised something. "GLaDOS, have you found out anything about why my letters and parcels are going astray? Hermione and the Weasleys said they sent things, but…"

" _I believe I have found the culprit at last. They were a tricky little customer, managing to avoid my cameras. However, as you know, I have found a way to emulate Will-based Transmogrification Force in this body, or magic to those too lazy or unscientific to recite the full name or acronym._ "

"I know, you've been practising Apparition with that body. You used it to come in here."

" _Exactly. Apparition causes a brief but acute distortion in local space, as opposed to the longer but less-straining influence of portals. I have calibrated sensors around Aperture to separate the two, and have found incidents of acute transient spatial distortion outside of my own use of Apparition. I have also excluded Mr Lupin and Mr Black, as they have not used it, outside of a few tricky Test Chambers, which I_ _ **still**_ _maintain is cheating. I have spotted a brief silhouette of our intruder. The outline conforms to a magical creature known as a House Elf._ "

"A House Elf," Harry mused. He had read about those last year, and nearly caused some trouble when he discussed them with Hermione. Only the revelation that they were engaged in a symbiotic relationship with the wizards they served to gain magic to maintain their existence stayed her hand, though she was still far from happy about it. Instead of freeing them, she was striving to find a way to give them rights, or at least protection against abuse. "Why would a House Elf steal my letters?"

" _I do not know. However, House Elves are generally owned by rich families, particularly those of a Pureblood persuasion. It is possible that this House Elf was sent to disrupt communications between you and your friends. However, said House Elf is unaware that Hermione can use email, and the Weasleys have been using the hologrammatic projector. Unless he or she is listening in._ " She stiffened, and then, her arm, quick as a striking cobra, suddenly lashed out and grabbed a hold of something just underneath the bed. Harry heard whimpering as GLaDOS pulled out a diminutive figure with large eyes, large ears, and wearing a rather ratty old pillowcase as a makeshift gown, which was how GLaDOS was holding him.

As the House Elf cringed away, GLaDOS said, almost conversationally, " _Good morning. If you wish for it to remain that way, you will introduce yourself, and explain what you are doing here. Otherwise, I may consider vivisecting you like I did to Mr Pettigrew a few days ago._ "

"Vi-vi-vi-vivisecting?" the House Elf whimpered.

" _In layman's terms, I will cut you up while you are still alive. Anaesthetic is optional, as is survival._ "

Harry leapt to the House Elf's defence, partly because it was the right thing to do, and partly because he was sure that GLaDOS was doing a 'good cop, bad cop' routine, where she was the bad cop. GLaDOS would never vivisect someone unless they had done something truly bad, and Peter Pettigrew had not just betrayed the Potters, but left Sirius to rot in Azkaban, and had murdered a number of people, a dozen alone when he framed Sirius for his own death. "GLaDOS, calm down! He's just a House Elf, he's not a Death Eater!" he protested.

"Harry Potter!" the House Elf whimpered. "So long has Dobby wished to meet you…such an honour…"

" _So, your name is Dobby_ ," GLaDOS said. " _We are making progress. As you have introduced yourself, and you know my great-nephew, I will introduce myself. I am the Genetic Lifeform and Disk Operating System, or GLaDOS for short. Keep in mind that I have the ability to become your worst nightmare, though at the moment, I have little of the inclination. If you explain what you are doing here, then that won't change._ "

"GLaDOS!" Harry snapped. He knew GLaDOS was bluffing, but he could tell how terrified the poor House Elf was. "Put him down."

Dobby, after a moment, looked at Harry, refusing to look GLaDOS in the eyes. GLaDOS rolled her eyes, but allowed Dobby to stand on the bed, though her hand still remained on his pillowcase gown. "You can sit, Dobby," Harry said. "I know House Elves aren't always treated so well, but as long as you're truthful…"

"Sit down…never…never ever…" Dobby began to sob loudly, even as he did so, GLaDOS shifting her hand as she did so to allow him to sit comfortably. "Dobby has never been asked to sit by any wizard, like an equal…"

" _Dobby, let us get back to the point_ ," GLaDOS said, her voice having a kinder tone than earlier. " _Are you the one responsible for stealing Harry's mail?_ "

After a moment, Dobby reluctantly nodded. "Harry Potter must not go back to Hogwarts. He will be in great danger! Dobby thought…if Harry Potter thought his friends had forgotten about him…he would not go back."

GLaDOS sighed. " _That is on par with one of Wheatley's ideas. Have you two been in correspondence?_ "

Harry groaned, and said, "Dobby…why do you think I shouldn't go back to Hogwarts? Is there something new happening?"

Dobby, reluctantly, nodded. "Dobby will have to punish himself later, but…Dobby knows of a plot, a plot to make most terrible things happen this year at Hogwarts…Dobby has known it for months, sir. Harry Potter must not put himself in peril. He is too important, sir!"

" _And who is behind it?_ " GLaDOS asked, only for Dobby to suddenly break free, and start hitting his head on the wall.

"BAD DOBBY! BAD DOBBY!" he shrieked.

GLaDOS rolled her eyes, and hauled the House Elf into the air again by his pillowcase gown. " _I presume it is your master, given your enthusiastic attempts to give yourself brain damage. House Elves are meant to protect their masters' secrets, and some punish themselves if they reveal them, or contravene their orders. You can't even reveal who your masters are, can you?_ " Dobby shook his head. " _Are they Death Eaters?_ " Dobby, after a moment, nodded, only to wince in pain. " _Well, you have done well enough warning us against their orders, Dobby. But I will put it to you bluntly. Harry will be returning to Hogwarts, and I will be going with him._ "

"But he mustn't! The great Harry Potter mustn't go back to Hogwarts!" Dobby protested. "He will be in mortal danger!"

" _Perhaps. But so will anyone else who crosses him, and by extension, me. Your warning has been heard, Dobby, but as a man by the name of Frank Herbert once said, knowing that there is a trap is the first step in avoiding it(_ _1)_ _._ " GLaDOS stood, lowering Dobby to the ground. " _You will come with me, Dobby, and you will see the consequences of crossing myself and my great-nephew._ "

"What are you going to do, GLaDOS?" Harry demanded, before she put his fears at rest.

" _I am going to show him a certain potato battery, and what is attached to it_ …"

* * *

Dobby's usually big eyes were now ridiculously wide as he saw the entity now informally known as Potatomort by the residents of Aperture. GLaDOS believed that he was torn between being afraid of Potatomort, being afraid of her, or being impressed by her. As Potatomort raged and raved, GLaDOS then turned to Dobby, and said, " _Do you understand, Dobby?_ "

Dobby nodded. "Dobby understands, Miss Gladys. But how did Miss Gladys manage such a feat?"

" _Harry captured him with Aperture technology. I was the one who made him into a potato. You are not to speak of it to your master, but then again, I doubt you will. You wouldn't want him to know you warned Harry, after all. However, you did so, and I thank you for it. If you will kindly return the letters you stole in your badly thought-out plan, I will let you go without attempting vivisection._ "

Dobby promptly fished a thick wad of letters, and laid them down with both fear and reverence, which appealed to GLaDOS' god complex. "He Who Must Not Be Named…is a potato. That thought will warm Dobby's heart for years to come."

" _I WILL ROAST YOUR HEART ON A SPIT, ALONG WITH THE REST OF YOU, HOUSE ELF! THEN WE'LL SEE HOW WARM IT IS…!_ " Potatomort roared as loud as he could, before his Personality Core shorted out and deactivated.

GLaDOS rolled her eyes, though she had to admit, the threat was halfway decent. " _We will take care, Dobby, and ensure that this plot will be stopped. And if I find out who your master is, I will endeavour to free you if you wish._ "

"Miss Gladys would do that for Dobby?" Dobby asked.

GLaDOS nodded. " _Now, go back to your master._ "

Dobby nodded, before disappearing. GLaDOS bent down and picked up the letters, before she turned back to Potatomort, who had just reactivated. " _Incidentally, Voldemort, how is potato-based immortality working out for you?_ " GLaDOS asked conversationally.

Voldemort's scream of fury could be heard across much of Aperture, though he deactivated for a lot longer that time…

 **CHAPTER 1 ANNOTATIONS:**

 **So, here you have it. The first chapter. It's quite a bit darker than the original, but I wanted to start with Harry's memory of GLaDOS activating. I decided to turn it into a nightmare. A bit clichéd, but effective. This flashback turned nightmare was born from waytodawn0's request in one of the reviews for** ** _Is Your Great-Aunt an AI?!_** **to show something of when Harry met GLaDOS. Unfortunately, I didn't do the whole thing, as it degenerated into a nightmare.**

 **I also wanted to show a more conventionally loving GLaDOS, one who occasionally does do these maternal things for Harry. Not often, but enough that his love for her is very real. Hopefully, the next chapter will have more humour in it. Incidentally, more will be made of how she came to be able to use magic later, although I did say it was possible at the end of** ** _Is Your Great-Aunt an AI?!_**

 **1\. A quote from** ** _Dune_** **.**


	3. Chapter 2: Who're You Gonna Call?

**CHAPTER 2:**

 **WHO'RE YOU GONNA CALL?**

After breakfast, GLaDOS convened a meeting between the various residents of Aperture Science, or at least those who could talk in anything other than binary. Or shoot bullets, otherwise, she'd have to invite the Turrets. Or were an overt and intentional threat to life, other than herself, so Potatomort was out. That meant Harry, Chell, Sirius, Remus, Rattmann, Gordon Freeman, Wheatley, and Myrtle. They were seated around a desk, with GLaDOS' main body hovering above, her gynoid proxy having gone to recharge.

"So, lemme get this straight," Gordon said. A neurotic, lab-coated man with a neat, fussy beard, he had gotten used to life in Aperture, dividing his time between research, Test Chambers, and being GLaDOS' lover. He had gotten used to the first and third roles. "Some magical servant thing that looks like the mutant offspring of Yoda and one of Santa's helpers has been stealing Harry's mail and making vague warnings about some dastardly plot of doom."

" _Yes, that is what I got through explaining, Doctor Freeman. Clearly, those years of education at MIT have not gone to waste_ ," GLaDOS said wearily, not bothering to hide her sarcasm.

"Well, summarising the situation aside, I've got a really important question: where can I get a House Elf? They sound really neat and all, and maybe it could be a good lab assistant, as well as all-round servant. I deserve the pampered life!"

"House Elf sales are highly regulated," Remus Lupin, a tired-looking man with scars, explained. "They are also expensive. I know Aperture could potentially afford several, but they almost always only sell them to Pureblood families."

Rattmann, who had a scraggly beard and nervously dancing eyes, said, "It sounds like slavery, even with this whole magical symbiosis thing."

"House Elves are generally treated well enough," Remus said. "And their very culture, what there is of it, takes offence at payment and freedom, unless they have been badly treated. And even then, if they're still loyal, they still take offence. House Elves are considered the drudges of Fey society, and the Fey are said to use them as servants too, so they're partly to blame for it. I don't like it either, but the best thing to do is, if you have a House Elf, to treat them well."

Sirius snorted. "I can't do that with Kreacher," the dark-haired man with grey eyes snorted. His time away from Azkaban had been kind, and the madness once dancing in his eyes was gone. So too was his haggard demeanour. "He treated me badly, on my dearest mother's orders, and when I was staying at my old home before coming here, he was reluctant to follow my orders."

" _We are straying from the point_ ," GLaDOS said. " _Do not make me bang a gavel…that came out wrong. In any case, Rattmann, it is somewhat hypocritical of you to complain about slavery, given that I have robots tending to your needs._ "

"I never accept them!" the schizophrenic scientist exclaimed.

An electronic sigh emanated from the supercomputer. " _Anyway, the point is, Dobby has warned us about a plot. He could not tell us of who is directing it, or who it involves. I asked him, shortly before showing him Voldemort, whether it was Voldemort. He claimed no, but he seemed to indicate that wasn't the whole answer. As you pointed out, Mr Lupin, it is rich Purebloods who tend to own House Elves, and Dobby did confirm his master is a Death Eater, presumably one of those who escaped imprisonment in Azkaban._ "

"Bet you any money it's Malfoy," Sirius muttered darkly.

" _While that is a possibility, there are plenty of Death Eaters who managed to escape imprisonment by claiming to be under the Imperius Curse_ ," GLaDOS said. " _The Carrows, Crabbe, Goyle, Macnair…and there may be Death Eaters who may not have been caught in the first place, with Pettigrew being a particular case in point. Malfoy will be still on the list of suspects, but we cannot rule out any others. Also, keep in mind that while the wizards brag about how inescapable Azkaban is, I do not believe this to be the case._ "

Sirius nodded. "I never really thought about it at the time, but now, I think I could have used my Animagus form to slip by the Dementors. If I ever found out Pettigrew was at Hogwarts, I would have done just that. But you're right. Moody wouldn't forgive me for not looking at all the suspects. Assuming it's a Death Eater behind this, what do you think they intend to do at the school?"

"Probably cause chaos and havoc," Wheatley said. His proxy android looked like a tall, thin young man with blonde hair and glasses, and sky-blue eyes(1). "I mean, these guys are basically terrorists, right? So maybe it's a series of bombings or something?"

" _Thank you, Wheatley, for stating the obvious_ ," GLaDOS sighed. He did have a point. She doubted it would be anything as mundane as bombings. Hell, she doubted most of the British wizards knew about the September 11 attacks, which had happened ten months ago.

"Or maybe it's like the Chamber of Secrets," Myrtle muttered, the formerly-glum ghost girl looking somewhat more cheerier now she had a body. "When I was alive, there were all these attacks, and there was a message about the Chamber of Secrets being opened. I think I was the last one killed in those attacks."

"What is the Chamber of Secrets?" Harry asked.

It was Remus who answered. "Well, it's not something you'd find in _Hogwarts: A History_. I don't think I even heard anything more than rumour. I only stumbled across a few references to it by accident last year while I was looking through the library at 12 Grimmauld Place. You know about how Hogwarts was founded by the Four Founders, right?"

Harry nodded. "Godric Gryffindor, Rowena Ravenclaw, Helga Hufflepuff, and Salazar Slytherin. I also heard that a rift developed when Slytherin apparently got shirty about allowing Muggleborns into Hogwarts. Then again, history is written by the winners. The books claimed he was obsessed with Blood Purity, but it could be he was worried about witch-hunters learning about Hogwarts through Muggleborns blabbing by accident."

Remus nodded in his turn. "That could be possible, Harry, though too many Slytherins hold to Blood Purity ideals. The legend of the Chamber of Secrets holds that Slytherin made a hidden chamber that couldn't be opened by anyone save for a true heir. Said chamber holds a horrific creature that the heir would use to purge the school of anyone with impure blood. So the legends claim. We never found the Chamber ourselves, but despite our knowledge of Hogwarts, the Marauders didn't know all of its secrets."

" _We will notify Dumbledore about this. At the very least, forewarned is forearmed, to use the cliché_ ," GLaDOS declared. " _In any case, I may yet be in a position to be on the scene, so to speak, if something does happen. As you are aware, I have found a means to emulate Will-based Transmogrification Force. And as I bought a number of books on magic, I have spent time practising spells and abilities. I am at NEWT level, I believe, in many subjects, and have an unofficial Mastery in Charms, Transfiguration, and Defence Against the Dark Arts. I am going to enter into negotiations with Dumbledore to apply for the DADA teaching role, or at least assist the next victim…I mean, applicant. Failing that, I will apply for the Muggle Studies position. I read the assigned text, and whoever wrote that has a very poor working knowledge of Muggle achievements since the 1940s. The writer does not list nuclear weapons, space flight, computers, or breast implants amongst Muggle technology._ "

"I think the current teacher is Charity Burbage," Sirius mused. "She was married to a Muggle for a time, she probably knows about technology. The problem is, it's the Board of Governors who assign texts most of the time, and Malfoy's top of the tree. However, from what I know, DADA teachers assign their own texts, and they get replaced every year. I wonder who the poor berk who's volunteered will be?"

" _Why do the DADA teachers get replaced every year?_ " GLaDOS asked. " _It seems inefficient for such a vital subject to have a new teacher every year. It would disrupt students' education, not that an imbecile with a stammer who turns out to have a neoplasic growth in the form of a Dark Lord growing from his head would help matters._ "

"I heard rumours. Supposedly, the position is cursed," Sirius said. "How it happens depends. Sometimes, they die, like Quirrell did. Sometimes, they just have an accident. Other times, well, some dark secret gets let out, ranging from an embarrassing birthmark all the way to being caught in a broom cupboard with a student."

"Knowing my luck, if I ever got asked for the position, someone would out me being a werewolf," Remus said bitterly.

" _Yes…remind me to find a way of capturing Fenrir Greyback_ ," GLaDOS mused. " _As enlightening as the tests you have allowed me to perform have been, Mr Lupin, I feel a vivisection is needed in the interests of science. I am sure there are many who would rejoice if I vivisected Mr Greyback. I could even sell tickets. You would have complimentary entry, of course, Mr Lupin. In any case, we know of a plot, one that will affect Hogwarts, and that it is the work of a Death Eater rich or old enough to have a House Elf. Is there a registry of House Elves in the Ministry of Magic?_ "

Sirius shook his head. "Some countries in the ICW do, but Magical Britain has a wholly voluntary system. I'd bet that Death Eaters would keep their House Elves off the list, in case they wanted them to do some dirty work. Not that most of them would do so. House Elves are generally beneath their notice."

Chell rolled her eyes. The athletic young woman, the sole human woman here (GLaDOS and Myrtle didn't count, being formerly human), looked to be of Asiatic descent, dressed in the orange jumpsuit of Aperture test subjects, though she kept the top open, revealing a singlet. And her athletic figure, which GLaDOS frequently mocked as being overweight, at best, which was obviously far from true. Chell's figure was quite attractive, and GLaDOS mocked merely out of routine than even any spite anymore. Taking her electrolarynx to her throat, Chell intoned in her buzzing tone, " _Death Eaters consider Muggles beneath notice, despite the fact that we have some pretty scary technology, even outside Aperture. It must be the inbreeding. I'm surprised you don't have webbed toes and a Hapsburg Lip, Sirius._ "

Sirius roared with laughter, or rather, he howled, befitting his canine Animagus form. Since coming to Aperture, he had a crash course in various scientific subjects, and genetics had proved enlightening. While he didn't understand it as much as his godson, never mind most of Aperture's inhabitants, he did understand enough to find the inbreeding prevalent in Pureblood bigots in general, and his own family in particular, hilarious, albeit darkly so.

Chell had also found herself in a friendship with the two surviving Marauders. Sirius was a bit more of an overt lech, but he was a decent man beneath it, more often than not. But she felt more of a kinship with Remus. It was born out of sympathy for his plight: Sirius had swiftly regained his self-confidence after being freed from Azkaban, but Remus had to live with his lycanthropy for much of his life, and had little self-confidence. And being the daughter of scientists, she actually preferred a more intelligent man, as long as he had compassion to match. And while Sirius did have the hots for her, once he realised she had more eyes for Remus, he subtly encouraged her. He probably recognised that he could have the pick of almost any woman he wanted, but few would want to be with Remus because of his lycanthropy.

The fact that she called his lycanthropy a more overt form of PMS helped break the ice. Quite by coincidence, Lily Potter had called it that too.

" _As much as I'd love to mock the incestuous tangled web that is the Black family tree, or rather, the Black family kudzu, we have strayed off track. Then again, we have nothing more to discuss on the vague evil plot of doom_ ," GLaDOS said. " _Although I may have convinced Dobby to leave Harry alone, we should still be on guard lest he tries to prevent Harry from going back to Hogwarts in spite of my showing him Potatomort. His fear of what his master may do may override his fear of my and Harry's prowess. Admittedly, we caught Voldemort by luck, but we caught him._ "

"So, Constant Vigilance, like Mad-Eye used to say?" Sirius asked.

" _Yes. Maybe I should meet this Mad-Eye Moody of which you speak, Mr Black_ ," GLaDOS said. " _He sounds like he rivals Rattmann in the paranoia stakes, only without the schizophrenia._ "

Rattmann scowled. He had taken his medication today, he wasn't that bad. And none present actually laughed at GLaDOS' joke, save for Wheatley, but he was an idiot anyway. Even Myrtle knew better than to laugh at the misfortune of a schizophrenic.

* * *

The meeting broke up shortly afterwards, and Gordon Freeman was walking to his new laboratories. That he got his own personal laboratory was a big boost to his already Brobdingnagian ego, and he considered that just compensation for being fired from Black Mesa. He might even forgive that pale spook in the suit GLaDOS called John Smith, and Rattmann called the 'G-Man'. For some weird reason, the latter name seemed more appropriate to Gordon, even though GLaDOS had admitted that it was unlikely that the G-Man was actually human.

Aperture was a nuthouse, sure, and he was discovering things that shouldn't exist by his knowledge of science. After all, three of the current inhabitants, not counting the two ghosts who were now AIs, were bloody wizards! Wizards! Magic existed, and while GLaDOS had done her best to try and find the mechanism involved (her best working hypothesis at the moment had something to do with virtual particles), it was still hard to pin down scientifically. It was no wonder she called it Will-based Transmogrification Force, with the succinct acronym of WTF.

And yet, once he got over the shock of magic being real, he realised, like GLaDOS had done, that this was a whole new frontier of science. Okay, given how anal retentive the wizards and witches were about maintaining secrecy, he couldn't exactly expect fame, fortune, and a Nobel Prize in his future, but Gordon, while rather disappointed, was still able to cope. The joy of discovery and working things out were reward enough. And at least here in Aperture, he was doing things, well, whenever GLaDOS wasn't roping him into going through Test Chambers. Whereas at Black Mesa, due to his junior status, he was stuck shoving specimens on trolleys into the Anti-Mass Spectrometer and other glamorous jobs. The one time he was let into the Lambda Complex, that creepy G-Man sabotaged the place, and blamed it on him.

Here, he had interesting subjects to research, cutting-edge equipment, and his boss was a three quarters-insane supercomputer whose gynoid body was smoking hot. What was more, recently, they entered into a more physical relationship, and he had to say, given his admittedly paltry experience with sex, it was actually pretty damn good.

Plus, the rest of the company wasn't so bad. Though he wasn't fond of Wheatley, Chell was all right, once she had made sure they could remain just friends. The mute woman was a bit of a looker, but she was also one of the sanest people in the place. The same couldn't be said about Rattmann, but Gordon was now used to the schizophrenic. He found replacement drinking buddies in Sirius Black and Remus Lupin. He found it hard to believe that he had two wizards, one of whom was also a werewolf, as drinking buddies, but that's the way the world went. He missed drinks and card games with Barney Calhoun.

Ironically enough, Barney's niece went to that Hogwarts place with Harry. The kid was a bundle of energy, scarily smart for his age…and yet, Gordon, despite his not being fond of kids, actually liked Harry. When they finally met face to face, the boy actually asked some pretty smart physics questions of Gordon, at a level that even some postgrad students would struggle with, and yet, the kid asked them seriously. Gordon also agreed to send emails to that niece of Barney's, who had, thanks to her parents, the pretentious Shakespearean name of Hermione. She was easily as smart, if not more so, than Harry. Looks like the little kid might have a girlfriend who'd be a match.

Still, the kid had a nemesis, had done since he was just one year old, who had the even more pretentious name of Lord Voldemort. Said nemesis, thanks to a series of events, was now an AI core attached to a potato, which Gordon, along with virtually everyone else in Aperture, found hilarious. Bastard was basically the wizarding equivalent of Hitler, so nobody really gave a damn, barring Voldemort himself.

Still, the biggest shock came in the last little while, when GLaDOS began to use magic herself. How can a computer do magic? Well, Gordon didn't know the hows, save for that GLaDOS managed to emulate the energy used for magic in her gynoid body…but he was willing to chalk it up to yet another surreal experience at Aperture…

 **CHAPTER 2 ANNOTATIONS:**

 **So, there you have it. GLaDOS and company have a plan, and Gordon's reflected on his time at Aperture. For those of you who skipped** ** _Is Your Great-Aunt an AI?!_** **, or the explanation in that story, this Gordon Freeman is the one from the spoof video series** ** _Freeman's Mind_** **. If you haven't seen it, and you're a** ** _Half-Life_** **fan, watch it. Imagine** ** _Half-Life_** **where you could hear a semi-deranged, neurotic version of Gordon Freeman. The maker, Ross Scott, may be doing a version with** ** _Half-Life 2_** **, but he intends to finish other projects first.**

 **Now, fans of the book will notice that the people involved do know some of the facts that get revealed later in the book. But they can't knit them together yet. The events will go off the rails PDQ, though…**

 **1\. I based Wheatley's human appearance roughly on his voice actor, Stephan Merchant. Of course, just about everyone else does.**


	4. Chapter 3: Who is Going to be Teaching

**CHAPTER 3:**

 **WHO IS GOING TO BE TEACHING DADA?**

Professor Albus Dumbledore pinched the bridge of his crooked nose wearily. Last Christmas, GLaDOS, formerly Caroline Evans, had delivered a holographic projector to Hogwarts in order to serenade the school with songs sung by her Turrets. However, she directed Dumbledore later to keep the holoprojector in case she needed to speak to him urgently. And while Dumbledore was grateful for that fact, the truth was, he still felt uneasy speaking to the AI with a loose set of morals.

That being said, she certainly had her heart, or whatever electronic equivalent thereof, roughly in the right place. Upon hearing of this warning from a House Elf, she had contacted him with the information. And he felt a certain feeling of dread. "That complicates matters, to say the least," Dumbledore said when GLaDOS had finished.

" _Your capacity for understatement is astonishing_ ," GLaDOS replied dryly, her gynoid form raising an eyebrow. " _What can you do about this?_ "

"Aside from informing my staff to be vigilant, surprisingly little," Dumbledore said. "I could alter the wards on Hogwarts to detect dark objects better, but given some of the artifacts in the school, as well as some of the things students smuggle in, there may be too many false positives. In any case, the wards of Hogwarts are both ancient and intricate. Attempting to alter them too much may cause a catastrophic failure. Focusing the search on Slytherin would also backfire. If the culprit is indeed a Death Eater, then they would probably try and find a catspaw outside of Slytherin, to deflect attention from them. This House Elf, Dobby, did he say anything else?"

" _No. He could not be specific. He seemed to be working hard to defy his master's will._ " The supercomputer's gynoid body sighed. " _I'm sorry I cannot be more specific, Dumbledore. I thought you would appreciate the warning anyway. Given the debacle with Quirrell last year…_ "

"I know. And I appreciate the warning, GLaDOS. Incidentally, is Harry all right?"

" _As much as can be expected. I believe he is suffering from mild PTSD from causing Quirrell's death and nearly being attacked by Voldemort. He is suffering nightmares, including of the incident in question, as well as my awakening in my current state. I am giving him what comfort I can give him, and the support of his friends and family help too. Incidentally, I am improving my ability to use magic._ "

Dumbledore, understandably, found it astonishing that the AI had learned how to use magic. He only learned about it about a week ago. He had spent that week contemplating something that could be a disaster…or a blessing. "And what do you intend to do about that?"

" _Experiment, of course. Between Mr Black and Mr Lupin's tuition, and the books I obtained, I believe I am at a high level of expertise. Given enough tests, I believe I could even teach at Hogwarts._ "

And there it was. Hesitantly, Dumbledore said, "If I and a Ministry official administer such a test, would you be willing and able to teach?"

" _Yes. My gynoid body is shielded against magic, and as you know, I can change the appearance of this body to suit the circumstances. Are you considering me for a position?_ "

"Officially, teacher's assistant for Defence Against the Dark Arts," Dumbledore said. "Unofficially, you might be able to do proper teaching of the subject."

GLaDOS' eyes narrowed. " _Why only 'teacher's assistant'?_ "

Dumbledore gathered himself, before explaining. "As you may know, every year, we have had to get a new DADA teacher. I believe that a jinx or curse has been placed on the position by Voldemort himself. The reputation of the curse is so much, few wish to teach in the position, and I would prefer not to call in favours from friends, lest I cause their demise, otherwise, I would have considered Sirius or Remus, or my old friend Alastor Moody. The only… _qualified_ applicant at the moment is Mr Gilderoy Lockhart."

GLaDOS frowned in thought. " _I believe I saw his books briefly at Flourish and Blotts. I paid little heed to them. Elucidate._ "

"Gilderoy Lockhart is a monster hunter of no small fame and renown," Dumbledore said. "He is famous for dealing with werewolves, banshees, and the like. However, it has come to my attention that he may be a fraud. Shortly after he applied for the position, I found myself remembering an incident from one of his books that happened to a friend of mine. When I asked my friend about it, he couldn't remember the incident. I found traces of a Memory Charm as well, and I remembered that, while a somewhat mediocre student for a Ravenclaw, Lockhart was gifted with Memory Charms."

" _I see. You believe he is a plagiarist who steals the credit from people who are better than he is. He reminds me of Doctor Breen at Black Mesa. He helped use industrial espionage to steal technology from Aperture_ ," GLaDOS said. " _Why not confront him?_ "

"He is famous and has cultivated connections to protect him," Dumbledore said. "Should I confront him, he would set his lawyers on me. He is good at covering his tracks, too. Despite my own fame, power and influence, I am far from untouchable. However, I was hoping to gather more concrete evidence of his wrongdoing while he teaches at Hogwarts. But I am worried about whether he is truly a competent teacher or not. Nothing in his books, aside from the plagiarised parts, suggests that he is incompetent. But I cannot shake the feeling that, if I let him teach, it may harm the education of the students. Which is why, despite my apprehension, I am glad you are confident that you can teach. Preferably without any physical harm to students."

" _You mean irreversible harm, surely_ ," GLaDOS said. " _Even given your fears about my…flexible morals, you know that most spells taught in DADA are reversible. I do not intend to teach the most dangerous curses willy-nilly, though I do intend to teach them one of the most vital elements in Defence Against the Dark Arts. Dodging. Incidentally, can we transform one of the classrooms into a paintball range?_ "

After a moment, Dumbledore said, "You're going to shoot at them with a non-lethal but painful Muggle device to teach them dodging, aren't you?"

" _It's good to see your reputation as one of the wisest wizards of your generation isn't wholly without merit_ ," GLaDOS replied.

Dumbledore, to himself, wondered if letting GLaDOS teach at all was a wise decision. Then again, between letting Lockhart have free rein and allowing GLaDOS to actually educate them, which he was sure was painful but effective…well, no contest, really. Though he had to wonder whether he had just entered some Mephistophelean pact…

* * *

"So…you're actually going to be teaching at this wizard's school?" Gordon asked not long afterwards.

" _By remote proxy gynoid_ ," GLaDOS said. " _I can control multiple gynoids at once, so if you are afraid for your sex life, don't be. In any case, if a teacher dares teach my great-nephew sub-par knowledge, then it behoves me to correct that._ "

Sirius frowned. Along with Remus, Chell and Harry, they were present while GLaDOS explained what she had learned from Dumbledore, as well as preparing to take a Portkey to the Ministry of Magic in Britain (MACUSA had different testing standards, and schools in Europe and schools in the US were loath to hire from each other, not helped by an incident involving Newt Scamander and Gellert Grindlewald) to submit to the DADA mastery test. Remus was creating the Portkey himself, as he knew where to go. "One," Sirius said, holding up a finger, "I don't really need to know about your sex life with Gordon here."

"Just 'cause you ain't getting any," Gordon muttered with more than a touch of schadenfreude.

"Hey, as the recently released and cleared Lord Black, I can have my pick of almost any eligible bachelorette in Magical Britain, or anywhere else in the world!" Sirius snapped back. "Anyway, two, is Dumbledore really sure that Lockhart is a fraud?"

" _He believes he may be a fraud, but he has little evidence beyond some circumstantial evidence. While Mr Lupin and I are in Britain, I intend to pay a visit to Diagon Alley and purchase his books. Dumbledore said that they would probably be on the textbooks list, as they are assigned by the teachers._ "

"They're more like glorified travelogues than textbooks," Remus said. "Expensive too."

" _I'll purchase a set for each of the Weasley children_ ," GLaDOS decided. " _I should also purchase some robes for myself. Then my transformation into GLaDOS, Dark Mistress of All Creation, shall be complete!_ " GLaDOS then laughed, the sound rather eerie given her lilting electronic tone. Then again, evil laughter could be eerie anyway. GLaDOS just elevated it into an artform.

"And what next, you'll conquer the world?" Sirius snarked.

" _Vi veri universum vivus vici_ ," Harry said. "One of Great-Aunt Caroline's favourite mottos."

Remus pursed his lips. " _By the power of truth I, a mortal, have conquered the universe_. Alan Moore claimed it came from Faust in _V for Vendetta_ , but it was actually the motto of a Muggle occultist, Aleister Crowley."

" _Good, Mr Lupin. You are indeed correct. At the time, I meant it in a similar manner to_ Scientia potentia est. _Knowledge is power. I intend to conquer the spheres of knowledge, Mr Black. I am, effectively, immortal thanks to those fools following Cave Johnson's last orders. I have all the time in the world to accumulate knowledge, and I now have the means to learn how to modulate Will-based Transmogrification Force. I would say 'nothing in the world can stop me now', but that would make me sound like a cut-rate villain from a cheesy comic book, not to mention tempting the universe to prove me otherwise. While it technically has no basis in physics, Finagle's Law does have a tendency to home in on hubris. Therefore, I should endeavour to partially emulate Uriah Heep, and be 'humble(_ _1)_ _'._ "

"I'd imagine, in comparison to Gilderoy Lockhart, you would be humble," Remus remarked. "Or at least you can back up your claims."

" _Of course I can. Backing up claims with evidence is the cornerstone of science. That, and deadly neurotoxin._ "

"No using neurotoxin on my classmates, please," Harry said. "They're unused to Aperture-style testing, even in Ravenclaw."

" _Harry, I can assure you, no Defence Against the Dark Arts lesson will use deadly neurotoxin in any way, shape, or form._ "

Remus frowned. "That was strangely and scarily specific. Are you going to expose your students to any kind of danger, beyond what is necessary for a DADA class?"

" _Given that being attacked by dark spells will cause death, many of which are of a painful and/or messy nature, your question is open to considerable interpretation. However, as Dumbledore will doubtless refuse me access to test subjects…I mean,_ _ **students**_ _, if the worst does happen, I will refrain from anything that will carry an unreasonable possibility of death and/or serious injury. Psychological trauma, however, is another matter. It is, after all, a cornerstone of operant conditioning._ "

"And don't forget the paintball guns!" Harry spoke up. "We haven't had a good match for a while, actually."

" _That was because Wheatley thought it would be a good idea to mix Gels into the paint for the paintballs_ ," GLaDOS reminded him. " _There are dangerous experiments, and then there is dangerous excremental idiocy._ "

"Didn't Cave Johnson pretty much straddle that line?" Gordon asked.

" _Very much so_ ," GLaDOS said. " _That's what made him a genius. Sadly, Wheatley doesn't straddle the line. He stays very much in Idiot Land most of the time. In any case, after I have confirmed my mastery of Defence Against the Dark Arts, we will start planning for going across to England. The Weasley family have extended an invitation to stay, and it will be at least moderately interesting from an anthropological standpoint to see a domicile belonging to mages. I should also like to visit your family's house for a comparison, Mr Black._ "

Sirius sighed. "You'll probably regret it. It's dank, dark, and aside from some pests, the only inhabitants are portraits and an ornery House Elf. Kreacher is not like many House Elves. He's nasty." Then, a nasty thought occurred to him. "Actually, do you want a House Elf to vivisect?"

" _That would be considerate of you. I am always on the lookout for specimens. And given what I have read about House Elves, they use Will-based Transmogrification Force far more differently to human mages._ "

On Harry's angry look, Sirius hastily said, "Look, Harry, most House Elves are nice and helpful. But a few are as nasty as any Blood Purist. He's always going on about his mistress, who is my late and unlamented mother, by the way. And who is now the most foul-mouthed portrait in the world. He always liked my brother Regulus better."

"Are we having some Freudian issues?" Gordon asked. "I mean, Freud was a bit of a nutbar, but he was a brilliant one at that. He had a lot of theories you couldn't disprove. You couldn't get away with that crap in physics…well, until Aperture gets involved(2)."

"My brother joined the Death Eaters," Sirius said coldly. "That goes way beyond anything Muggle shrinks can deal with…"

GLaDOS smiled, rather unpleasantly. " _Well, in any case, I would love to see your home, Mr Black, and I would also love to meet your mother and your House Elf. Though I am sure they will have cause to regret drawing my attention_ …"

 **CHAPTER 3 ANNOTATIONS:**

 **So, yeah. A bit more talking. We'll get to the plot in earnest in the next chapter.**

 **Incidentally, since I published the first chapters of** ** _Just How Can a Computer Do Magic?!_** **, Ross Scott has posted the first video of the new series of** ** _Freeman's Mind_** **, based now on** ** _Half-Life 2_** **. Ironically, he posted it on April Fool's Day, but the video itself is not a parody. Well, of anything but** ** _Half-Life_** **, but that's par for the course for** ** _Freeman's Mind_** **.**

 **Incidentally, I'm astonished at how swiftly this new story has gotten new favourites and alerts, and even C2s. I guess that shows how popular** ** _Is Your Great-Aunt an AI?!_** **was. Hope you enjoyed this chapter.**

 **Review-answering time!** **bissek** **: The problem is with the events of** ** _Dune_** **was that the Atreides didn't know who the traitor (Dr Yueh) was. They suspected what the Emperor would do, like bringing in Sardakaur, etc, and were trying to prepare themselves for their treachery. They got lucky in that they won enough respect from the Fremen and from Kynes (who was meant to betray the Atreides if they tried to flee for the Fremen) that Paul and Jessica managed to flee into hiding. Nice variation on the quote anyway. It's funny.**

 **waytodawn0** **: I'm not sure, but probably not. I don't think I have the wherewithal to explore more of the past there.**

 **LigerHorse** **: Hologram and holograph are pretty much the same things.**

 **BlazeStryker** **: Hmm, I dunno about Alyx, but Barney? Hmm, that's a possibility. It'll be a bit hard to justify their appearance, though…**

 **WhiteElfElder** **: I think Sirius would let Kreacher be vivisected, as seen above. And I think that Harry and GLaDOS did check Harry's finances, but they don't need them as much, as Aperture, thanks to what technology it does export, has enough money to run itself and have plenty left over.**

 **1\. Uriah Heep was one of the villains in Charles Dickens' famous novel** ** _David Copperfield_** **. Although a clerk who claimed to be 'umble, but was really a nasty, hypocritical sort, defrauding his employer and later partner Mr Wickfield and intending to marry his daughter.**

 **2\. Freeman's remarks about Freud were inspired by a similar monologue in Episode 13 of** ** _Freeman's Mind_** **.**


	5. Chapter 4: Does Retail Therapy Work?

**CHAPTER 4:**

 **DOES RETAIL THERAPY WORK?**

Harry knew that Molly Weasley didn't know quite what to make of GLaDOS, or Gordon Freeman for that matter. Then again, the same could be said for Arthur Weasley, but he at least enthusiastically ploughed through, even in his ignorance. Molly looked GLaDOS up and down, frowning. "So, you are Harry's great-aunt?"

" _Your powers of observation do you credit_ ," GLaDOS remarked dryly. " _I am also helping teach your children Defence Against the Dark Arts._ "

"And, from what I can gather, you are a golem of some sort? One with the mind of a Muggle in it?" Arthur asked.

" _Yes. It is considerably more complicated than that. If it makes you feel any better, the scientists who did this to me were of an appallingly amoral sort_ ," GLaDOS said.

"It doesn't," Molly said, looking a bit wary of the AI.

" _Perhaps that is for the best. Rest assured, I will do my utmost to ensure that your children are well-versed in DADA_." Now, Harry knew that GLaDOS was very tempted to make a snide remark about Molly Weasley's weight, the fact that her family was somewhat poor, and, in spite of such financial troubles, she had had seven children. However, GLaDOS was trying to be tactful, and decided to restrict her snark to comments that wouldn't get her hexed, or Harry unable to remain friends with Ron.

Of course, Gordon wasn't the same. "So…what's with the weird clock?" he asked. "Pretty crappy clock if it can't tell the time."

"Language," Molly huffed. "And for your information, Doctor Freeman, it shows the status of my family."

"Hey, don't get me wrong, it's a cool gizmo and all, handy with a big family, but, well, I like clocks. I'm a physicist, I like knowing what time it is, even if it's all messed up by relativity. And international time zones."

On Molly and Arthur's looks at Harry, he shrugged. "He's like that. But he's a foremost authority on energy physics and teleportation."

"You said it!" Freeman said, beaming, before looking a bit sad. "Man, Kleiner's probably having fun with his experiments without me."

Ron, who was coming back in after going to fetch something, said, "Your friend's mental, Harry."

"Says the twelve year old wizard," Freeman scoffed at the redhead. "Seriously, you're a bloody wizard. I spent my university degrees disdaining the possibility of your existence, and yet, here you are. I'm glad GLaDOS actually had some papers for me to read up on, because otherwise, this'd be too much of a paradigm shift for me to cope with. I'd definitely BE mental."

On their blank looks, GLaDOS said, " _A paradigm is a worldview. Doctor Freeman is merely saying that it's hard to believe, given that he is a scientist. Incidentally, I will be purchasing the supplies your children need for this year. And if you dare protest, I will be offended_." Her eyes narrowed. " _Do_ _ **not**_ _offend me. The last person to do so became a potato._ "

"As in, you transfigured him into a potato?" Molly asked, aghast.

"Wicked!" Ron breathed in awe.

" _Not exactly. Mr Weasley, are you versed with the basic scientific experiment of creating an electrical cell, what most people would call a battery, with a potato or a lemon, wiring, and two different metals?_ "

"Umm, no. Should I be?"

GLaDOS, after a moment (pinching the bridge of her nose in the process), said, " _You are meant to be an authority on Muggle artifacts. I think I will send you highschool textbooks on science and technology, and you are going to_ _ **read**_ _it._ "

Molly's angry protest was cut off by Arthur yelping, excitedly, like a kid told he had unlimited credit at a candystore, "Really?"

" _Did I stutter? I am GLaDOS, not SHODAN(_ _1)_ ," GLaDOS sighed. " _In any case, when do we intend to head to Diagon Alley?_ "

"Before long," Molly said, managing to regain her handle on the moment. "Ron, are the others ready?"

"I think the Twins were trying to prank Percy," Ron said. A yelp of anger from upstairs, followed swiftly by laughter, punctuated the point. "Ginny's still a bit…"

"Shy?" Arthur said with a sigh. He looked at GLaDOS. "I'm sorry, but Ginny…she's got a hero-worship thing for Harry. We've tried telling her the books are nothing like the reality, but…"

"As long as she doesn't want my autograph, I'm fine," Harry said.

"Ooh, sounds like you've got a fangirl, Harry," Gordon teased.

* * *

GLaDOS tumbled out of the Floo in the Leaky Cauldron in an undignified, soot-smeared heap, and scowled. As the Weasleys and Harry stared at her, along with many other clients in the pub, she said, " _You. Saw. NOTHING._ "

Harry hid the digital camera he had used to take photos of his great-aunt's tumble. He had to send them to Chell later, along with Rattmann. They'd get a laugh out of it. One of the clients of the pub muttered, "Tourist."

GLaDOS got to her feet, and glared at the impertinent man. " _And you are a classic example of the inverse relationship between the size of the mouth and the size of the brain(_ _2)_ _._ "

"WAAAAHHHH!" screamed Gordon as he tumbled out of the Floo, right into GLaDOS, sending her crashing to the floor again. As he got to his feet, staggering, he slurred, "I'll never be cruel to an electron in a particle accelerator again(3)." Then, he vomited copiously onto Harry's shoes.

The publican, Tom, sighed a long-suffering sigh, before saying to one of his offsiders, "Mavis? We've got a Code Green at the Floo. _Again_."

* * *

As expected, Molly protested against GLaDOS insisting on purchasing essentials for the Weasley children. It was Arthur who managed to persuade her to accept the help.

" _In any case_ ," GLaDOS said, " _consider it payment for my anthropological observation of a typical Pureblood family._ "

"Anthro-what?" Molly asked.

"Ignore her," Harry said. "Look on the bright side, Ron. You can get your own wand now."

Ron looked embarrassed, but also relieved. Ginny managed to pluck up the courage to ask, "Harry…why does your great-aunt have so much money?"

"Aperture is one of the leading R&D facilities in the world. Okay, it's pretty secret, but…"

"R&D?"

"Research and development," Harry explained. "They create new machines and medicines and the like. Very little of what Aperture makes does get sold, partly because it'd be too expensive to manufacture properly, and partly because it's too dangerous, but what we do sell sells a lot. Most of the money goes back into funding Aperture, dealing with maintenance, etc. GLaDOS is a better CEO than Cave Johnson, though." Which wasn't too hard, Harry reflected, given how much of a profligate spender Cave had been, and on useless ventures too.

"Hey, GLaDOS," Ron said. "If Lockhart's teaching DADA this year, why are you teaching?"

GLaDOS frowned, before saying, " _Let me answer your question with a question, Ronald Weasley. Have you read his books?_ "

"I've read a couple of them," Molly said, while Ron shook his head.

" _Ah, capital. He has assigned his books as 'textbooks', and yet, they are, at best, self-indulgent travelogues that, while enjoyable and having some anecdotes of use, nonetheless serve purely to pander to Lockhart's ego_ ," GLaDOS said. " _They are NOT textbooks. The thought of even considering them as such makes me want to vomit as copiously as Doctor Freeman did in the Leaky Cauldron, and this body is not designed for any kind of emesis. In addition, Professor Dumbledore is concerned about the inconsistency of DADA teaching over the years. Therefore, he assigned me as a teaching assistant._ "

"And you can do magic?" Ron asked sceptically.

" _I have certified masteries in most areas of magic. I made sure I was tested over here, as well as back home in the United States._ "

"Wouldn't that be a kick in the face to Malfoy and the Blood Purists?" Arthur muttered. "I didn't think such a thing was possible."

"We have a saying in Aperture," Harry said. "The impossible is merely something we haven't tried to do yet…"

* * *

It was good to be reunited with Hermione, Harry reflected. She had been at Gringotts with her family, changing over pounds to Galleons, and while Arthur goggled, Harry took a moment to say hello to Hermione, as did Ron. While Arthur peered at the pound notes the Grangers and GLaDOS changed over, fascinated, and asked frankly inane questions, Hermione saw Doctor Freeman, and gasped. "It's good to see you again, Dr Freeman!"

Freeman grinned. "It IS good to see me. Hey, you're the girl Harry had me email, the one who wanted my signed paper. Hermione, huh? Barney's niece? Heard anything from him lately?"

"He's moved over here," Hermione said. "Apparently he turned whistleblower against Doctor Breen's industrial espionage a little while ago. He can't work at Black Mesa anymore, though. I dunno where he went, though."

"Actually, I was talking to some of the guards. Got curious about what being security at a wizarding bank was like," drawled a voice familiar to a few of those present. A dark-haired man with a pleasant face, dressed in a blue shirt, came forward. "Wow, Gordon. You're still alive and intact. I'd have thought that damned crazy computer would have cut you up by now."

"Hey, you know better than to underestimate the Freeman," Gordon chortled. "Damn, Barney, you turned state's evidence against Breen?"

"Yeah. After you got that kangaroo court thanks to that spook in the suit, Breen started going loopy. I'm not the only one who blew the whistle, I was just the one who had to do the dirty work. Dr Vance, Dr Kleiner, they also helped as well. But, well, someone had to fall on his sword to take out Breen, and I chose to do it." He looked at Harry, before smiling softly. "Hey, kid. I'm glad you're still alive and well too. How's Chell?"

"She's all right. So's GLaDOS. I'm sorry to hear that you're no longer working at Black Mesa, Barney," Harry said.

"Meh, I'm fine, kid. Between Aperture and Black Mesa, I'm sorta sick and tired of dealing with top secret R&D places. I managed to get a decent job as security at Gatwick Airport. That creepy spook in the suit helped smooth things over. You know, the one who talks funny and looks like he's never seen a day's sun in his life."

Ron asked, "Who's he talking about?"

"Oh, he means John Smith," Harry said. "Creepy guy, might not even be human. Rattmann calls him the 'G-Man'."

"The G-Man?" Ron echoed.

"Because he looks like he's from the FBI or CIA," Harry explained. "Like he's a spy or a top Auror."

"Oh."

* * *

Later, Hermione and Harry, along with Freeman and Barney, were walking down Diagon Alley. Ron and Ginny had been taken away by Molly and GLaDOS to get new robes and wands, Arthur had taken the Grangers to the Leaky Cauldron to get more information about Muggle things from them, and Percy had gone off to buy his own supplies. The Twins, meanwhile, had gone off with Lee Jordan, their friend. As they made their way through Diagon Alley, Hermione asked various questions of Gordon, mostly about physics, while Harry asked Barney about his career at Black Mesa.

After browsing the various shops for some time, the quartet, finally joined by the Twins, headed to Flourish and Blotts, where they found a large crowd for a book signing. Lockhart was signing his autobiography. Hermione, much to Harry's annoyance, was going all fangirly. Thankfully, they managed to get into the shop, and found their guardians waiting in line, GLaDOS already having gotten the books. The gynoid was getting some looks for the way she casually carried a large stack of books with seemingly little effort. With one hand, in fact.

And there, at a table, was Lockhart, a blonde, handsome wizard, with a near-perpetual smile on his face. Especially as he was being photographed by someone from _The Daily Prophet_.

Of course, it went downhill when Lockhart spotted Harry, and grabbed him to drag him over for a photo op. "Nice big smile, Harry. You and I," he said, "are worth the front page."

" _Yes_ ," GLaDOS said, having come over with her books in hand. " _I can see the headlines now:_ _BAD TOUCH! Boy Who Lived Molested By Rapacious Fop_ _._ "

Lockhart frowned. "And you are?"

" _Professor Gladys Johnson_ ," GLaDOS said.

"Ah, my glamorous assistant! Dumbledore never told me how much of a paragon of beauty you were!" Lockhart said, his habitual smile returning. "Come here, come here!"

GLaDOS rolled her eyes, before joining him. As they smiled for the camera, GLaDOS whispered, " _Do not grab my great-nephew and drag him into one of your grandstanding opportunities again. Otherwise, during the classes, you're_ _ **target practice**_ _._ "

Lockhart's smile became a touch fixed, before he then announced, "Well, ladies and gentlemen, it's the perfect moment for me to make a little announcement, one I've been sitting on for some time! When young Harry stepped in this illustrious store today, he only wished to buy my books…which I will give to him signed, and free of charge…but he had no idea he would be getting more than a chance to meet me! He, along with his friends and peers at Hogwarts, will be getting the real me! I have great pleasure and pride in announcing that, this year, I will be taking up the Defence Against the Dark Arts post at Hogwarts! Assisted by the very lovely and able, I am sure, Gladys Johnson!"

The applause was loud, and eventually, Harry, along with the others, managed to get out of the crowd to a quiet corner after paying for the books. But even as they tried to collect themselves, they heard an unwelcome drawl. "Bet you loved that, Potter?" Draco Malfoy asked.

" _Anyone with half a brain or more would have been able to tell otherwise_ ," GLaDOS said, looking at the blonde-haired boy.

"I have nothing to say to a Muggle," Draco sneered. "You shouldn't be teaching."

" _I have magic. And even if I did not, I am sure I would raise the tone of Hogwarts by being present_ ," GLaDOS said. As Draco opened his mouth to say more, GLaDOS said, " _Consider your next words very carefully, for I will be teaching you, and I may consider some deferred penalties for your insolence_."

"Draco, that's enough," came a sharp voice, and a man with the same sharp features and blonde hair as Draco came through the crowd. He peered at those present, his eyes focusing on GLaDOS briefly.

" _You must be Lucius Malfoy_ ," GLaDOS remarked.

"And you must be the…woman they have hired to shore up Lockhart's foolishness," Lucius Malfoy responded. He went over to Ginny's cauldron, the one holding her supplies, and fished out a number of books. "New books? My, you must have had a windfall I wasn't aware of, Arthur." His eyes then flickered over to GLaDOS. "Or perhaps you have a benefactor who throws good money after those who are a disgrace to wizards everywhere?"

Arthur then said, "You and I have very different ideas of what disgraces the name of a wizard."

As Lucius Malfoy opened his mouth to reply, GLaDOS held up a finger. " _If you are going to make some remark about the company he keeps, keep this in mind, if you have one. You are the head of your family, in a crowded bookshop, with a photographer from the press, and your next remarks could start a brawl. Does annoying Mr Weasley sound like a good idea? Does annoying_ _ **me**_ _?_ "

After a moment, Lucius merely sneered, and said, "Come along, Draco. We won't mingle with the rabble any longer."

As the two blondes left the store, GLaDOS rolled her eyes. " _Does all that hair bleach they must use lower their intelligence quotient? Or is that the shallow, incestuous puddle they call a gene pool?_ "

"More of Column B," Harry mused. "I thought I managed to get Draco to be a bit nicer after I got him that Christmas present last year."

GLaDOS rubbed her chin thoughtfully. " _Hmm. I think someone has volunteered for target practice for the entire year._ "

"Target practise?!" Emma yelped. "Spells or bullets?"

" _Paintballs, Dr Granger. Do not worry. I will not cause any physical injury, beyond bruising, or any possible death_ ," GLaDOS said, before she gave a vicious smirk. " _However, I believe that by the end of the school year, his ego will have died a slow painful death._ "

"Wicked," breathed Ron in awe.

"Indeed, Ronniekins," Fred said.

"We have found ourselves outmatched, Fred," George said.

"What sort of example are you setting for my children?!" Molly demanded.

" _The kind of example all examples should be: instructional. Now, shall we be off? Only, I find being in close proximity to someone with the ego of Cave Johnson and the intelligence of Wheatley rather draining on my own IQ…_ "

 **CHAPTER 4 ANNOTATIONS:**

 **So, there you have it. This time, Harry didn't have his little sojourn down Knockturn, and we've had GLaDOS making snarky commentary. Oh, and we've got Barney! I wasn't planning on bringing him into it, and he's closer to his incarnation in** ** _Half-Life_** **than in** ** _Barney's Mind_** **, but hey, we've got enough crazy, between GLaDOS, Wheatley, Rattmann and Freeman.**

 **Now, in the most recent episode of** ** _Freeman's Mind_** **, Freeman only seems to know Dr Kleiner, with Barney, Breen, and Vance not being known to him (Ross Scott, apparently, said that is due to Kleiner being the only one canonically named in** ** _Half-Life_** **, in the manual of the game). Because I've already had Freeman mentioning socialising with Barney, I decided that, for this story, Freeman knew the personnel named in** ** _Half-Life 2_** **.**

 **Review-answering time!** **AnFan-n-More** **: Sadly, Richard won't be appearing. I went off** ** _Looking for Group_** **after one of the main characters died, and the fallout from afterwards. And I won't be crowbarring him in.**

 **Ultimate-Zelda-fan** **: Hmm, maybe she will make like Abridged Piccolo.**

 **Skyfish104** **: It's back in this chapter, I think. This GLaDOS was kept more human by Harry, and she was more sarcastic in the previous story,** ** _Is Your Great-Aunt an AI?!_** **, so if you haven't read that, then go do so forthwith.**

 **1\. AKA the villain of the** ** _System Shock_** **games, another megalomaniacal female AI known for stuttering her words. Both games were released well before this story's setting (2002, ten years ahead of canon for Harry Potter), so GLaDOS may know of them.**

 **2\. The Doctor uses this line in** ** _Doctor Who: The Robots of Death_** **. Perhaps unwisely, as the man he insults with it promptly tries to strangle him.**

 **3\. Another** ** _Doctor Who_** **reference, although one that will sound familiar to fans of** ** _The Hitch-Hiker's Guide to the Galaxy_** **. The Doctor says this in the Douglas Adams-penned** ** _The Pirate Planet_** **while whizzing down an inertia-nullifying corridor. Adams modified the joke for** ** _The Hitch-Hiker's Guide to the Galaxy_** **.**


	6. Chapter 5: How Can the Kings Cross

**CHAPTER 5:**

 **HOW CAN THE KINGS CROSS BARRIER BECOME IMPASSABLE?**

Lucius Malfoy smirked. His plan had succeeded, so far. True, he couldn't slip it into the cauldron of the Weasley girl like he initially wanted to at the bookshop, so he couldn't discredit one of his enemies. That damned Johnson woman had been watching him like a hawk, and something told him he couldn't get away with it. Instead, he found someone else not long afterwards. Someone else who was, perhaps, a better patsy than the Weasley girl. It would probably make for a better plan this way, to discredit the worst of his political opponents by showing the dangers of Muggleborns…and to oust that fool Dumbledore.

Still, that Johnson woman…as barely-veiled as her threat had been, Lucius knew that the woman had some power. She spoke with a confidence any true Slytherin would envy, despite being apparently a Muggleborn, and an American, which compounded the issue. She was certainly dangerous, and her ability to discern that Pettigrew was the true traitor (something even Lucius wasn't privy to) and exonerate Sirius Black showed her to be no fool. Ditto Harry: he was a Ravenclaw, and he had also not actually overtly rejected Draco's overtures, despite Draco viewing them as a snub. The Boy Who Lived, despite living in some isolated Muggle facility in the Colonies, was a canny operator.

Still, he had to wonder, would they be able to find out what was causing the attacks once the Chamber of Secrets re-opened? They certainly shouldn't be able to connect it back to him, though. Nobody was that good…

* * *

The trip to King's Cross had been performed in something of a rush, and Harry, GLaDOS, Ron and Freeman were the last to make the trip through the barrier, with them on the verge of running late. "So, this barrier thing, it's a secret passage through that support pillar?" Freeman asked, as quietly as he could, given the noise of the crowd.

" _Covered with the Will-based Transmogrification Force equivalent of a Somebody Else's Problem field(_ _1)_ ," GLaDOS remarked. " _We had better hurry._ "

The Weasley family, barring Ron, had already gone through. But GLaDOS, Freeman, Harry and Ron were moving forward, only to bounce soundly off. GLaDOS regained her footing with less dignity and ease than she would like, and scowled. "Okay, I have to ask, does it require a password? Like 'Open, Sez Me'?" Freeman asked, as he recovered his own footing.

"Of course it doesn't!" Ron said irritably. They were attracting attention too. Unwanted attention for that matter.

GLaDOS gently pushed the trolley she had forward, until it nudged where the entrance was supposed to be. Her eyes flickered up to a clock, and her scowl worsened. " _Something has sealed this barrier_ ," she said. " _I can sense it._ "

"The train's left," Ron bemoaned as he took note of the time too. "What're we going to do?"

"Should we wait by that car?" Freeman asked. "Didn't your dad say it could fly or turn invisible or something?"

As Ron's eyes lit up with an idea, GLaDOS shot him a look. " _No. We are_ _ **not**_ _taking the car. It is a bad idea comparable with one of Wheatley's._ "

"But under emergency circumstances…" Ron began.

" _I have one word to say to you, Ronald Bilius Weasley: Apparition._ " GLaDOS smirked, before turning to Freeman. " _Dr Freeman, wait here for the others to come out. If and when they do come out, notify them that I am taking these two via Apparition to Hogsmeade with Harry and Ron. Dumbledore provided me with a memory for Apparition coordinates to Hogsmeade._ "

"Got it. You're using freaky wizard teleportation to get to Hogsmeade. Hey, how long do I wait before I take the Portkey back to Aperture, then?"

" _As long as it takes for the Weasleys to come out_ …"

* * *

With a loud crack that rattled the windows of the nearby houses, GLaDOS, Harry, Ron and their luggage, including their owls, appeared in Hogsmeade. Harry shook his head. "Is it me, or is all wizarding transport uncomfortable? I mean, the Floo, Apparition, Portkeys…"

"Don't knock it, your great-aunt got us here," Ron said, though he swayed slightly. "What're you going to do?"

" _Professor Dumbledore still has that holographic projector I sent. I am sending him a message._ " She closed her eyes and concentrated.

"So what do you think happened to the barrier?" Harry asked Ron after an uncomfortably long period of silence. "Does that normally happen?"

Ron shook his head. "The portal to the station does close outside of the times the Hogwarts Express is used, but…never that soon. Not that I know of, anyway. Dad and Mum told us how to do it, and I've been to the platform for a few years before I went. Nothing like this had ever happened."

" _I have a hypothesis, though it is still a work in progress_ ," GLaDOS said, opening her eyes. " _Dumbledore is sending House Elves to fetch our luggage, save for your familiars._ " With pops, the trunks and bags vanished. " _Efficient,_ " she noted. " _We will head on up to the castle. Professor Snape will meet us on the grounds_ …"

* * *

The relationship Harry had with Severus Snape was an odd one. Snape had spent many years bearing a grudge towards Harry's father, and holding a torch (according to Sirius and Remus) for Harry's mother. What was more, the man had a tendency to unfairly favour members of his own House of Slytherin, and his teaching ability, in the end, was nothing to write home about.

That being said, Harry respected the man's intelligence, and after discussing elements of potions with him, Snape reciprocated, grudgingly at first, but over time, he had become, if not warm to Harry, then at least helpful in small regards. It probably helped that Harry ended up in Ravenclaw rather than Gryffindor, a House Snape despised. So while their relationship wasn't actually close, it was certainly cordial, though Harry detested his bias against Gryffindors, and against the hapless Neville Longbottom in particular.

They met him halfway up the path to Hogwarts, the man's dark robes billowing about him as he strode forward in his usual imperious manner. "It seems that you can't make it beyond the Start of Term Feast without causing some sort of scene, Evans," the greasy-haired man remarked dryly as he approached. "I had been hoping for things to go wrong only by or after Halloween. Still, at least it seems someone had some sense in their head."

" _Sadly, common sense is an oxymoron in the world_ ," GLaDOS said. " _What will they do until the feast?_ "

"Filius will babysit them," Snape said. "Merlin knows that he needs a break from listening to that attention-seeking fop Lockhart. I certainly do. How he ended up in Ravenclaw, I've no idea…"

* * *

"It's weird being here before all the others, innit?" Ron asked as he and Harry, under the watchful eyes of Professor Flitwick, played chess as they waited.

"Yeah. Well, actually, it feels more like home. Home's pretty large, and yet empty," Harry said wistfully, thinking of Aperture. The Great Hall certainly did seem eerie when it was empty. It reminded him of the various abandoned and derelict rooms at Aperture Science. "So, where do you think your sister's going to be Sorted?"

"Gryffindor, obviously."

Harry nodded. He then remembered a meeting he had, the day before they were due to leave. One of the Weasleys' neighbours, Xenophilus Lovegood, had come back from some overseas trip, and he had visited, along with his daughter, a rather dotty girl by the name of Luna. Harry and GLaDOS, despite the girl's fantasist leanings, actually liked her: she seemed slightly insane, but in a good way, albeit one that wouldn't seem out of place in Aperture. And she was an excellent lateral thinker. "What about Luna?"

"Her? Well, I'd guess Ravenclaw: her mum and dad were both there, even if they're barmy as anything. Apparently her mother died while spellcrafting, though, and Luna saw it happen," Ron said, looking rather solemn at that. "Hey, maybe you and Hermione could help her out if she does get Sorted into Ravenclaw. She's been pretty lonely. Ginny's really her only friend there."

"And you're not?" Harry asked.

"Luna's…a bit too weird for my liking."

"So am I," Harry pointed out.

"Yeah, but you're also able to back it up, mate. She goes on about these animals that don't exist, and makes up these conspiracies about the Ministry. Look, I don't hate her or anything, I just don't deal with her weirdness well."

"Even so, Mr Weasley," Flitwick piped up from where he was sitting nearby, "absence of evidence is not evidence of absence. Or, in layman's terms, just because you cannot see it does not mean it doesn't exist. I admit, some of what Xenophilus and his daughter write about in _The Quibbler_ is more than a little fanciful, but for those with keen minds and eyes, it holds a wealth of information that the _Prophet_ would not touch. That being said, Mr Weasley is right in one regard: from what I know, Miss Lovegood has few friends, and her views may alienate her from the more…pedestrian minds of Ravenclaw. Would you mind helping her get used to things, Mr Evans, should she be Sorted into Ravenclaw?"

"Does E=MC squared?" Harry asked wryly.

As Flitwick chortled, Ron looked askance at Harry. "What?"

* * *

"This is disturbing news indeed," Dumbledore said. GLaDOS had been brought by Snape to the Headmaster's office, before the greasy-haired man left to work on some potions.

" _Your grasp of the obvious never fails to astonish me, Professor_ ," GLaDOS snarked. " _What is more, the energy signature I picked up seems to be identical to the House Elf Dobby. I cannot say for sure that it was the exact same signature, as I am yet to compare it to other House Elves. But it certainly was not human Will-based Transmogrification Force. And given Dobby's earlier insistence on Harry not returning to Hogwarts, I believe he may have recovered his courage and made an overt attempt to stop Harry._ "

"Do you have any proof?"

" _Aside from the energy signature, none whatsoever. It could be a malfunction on the portal, true, but while I am an artificial sentience that relies on logic, even if it is twisted, I still have intuition, and my intuition tells me that this was deliberate._ "

"True. Already, Dobby stole Harry's correspondence. Despite you showing him Voldemort, he may have regained his courage. The question is why, and what danger he was trying to warn you and Harry about."

GLaDOS nodded, before deciding to change the subject. " _I must confess, I am singularly unimpressed by what I have seen of Lockhart so far. I will have to work overtime to try and prevent his incompetence from hampering the students, particularly those intending to sit for their OWLs and NEWTs. Still, I have significant experience dealing with morons with high opinions of themselves. Wheatley springs to mind._ "

"As much as I hate to say it, I agree. I had hoped that Gilderoy had actually picked up some qualifications through means other than Memory Charm-assisted plagiarism. Unfortunately, he was the only applicant. If he doesn't make it through the year, I will have to call on friends for favours. Remus, for one. And Alastor for another. In fact, given the quality of his essays in school, I have to admit to wondering whether he had his books ghostwritten."

" _The information in them is useful, once you discard the parts that are basically glorified travelogue_ ," GLaDOS mused. " _But they still had no business being assigned as textbooks. For example, he does not state that the Homorphus Charm is only a_ _ **temporary**_ _measure for dealing with werewolves. In fact, he implies the reversal to be permanent. Incidentally, Mr Lupin has been kind enough to allow me to investigate how his transformations work, and while results are still, for the most part, pending, they are still quite fascinating. While I am uncertain of effecting a cure, I can certainly find a way to allow the werewolf to transform and retain their sanity with minimal loss of sanity. But back to my point. I will endeavour to mitigate the damage Lockhart causes to your students' education._ " A vicious smirk lit up her face. " _And I look forward to undermining him wherever I can._ "

Not for the first time, Dumbledore found himself questioning his decision to allow GLaDOS to teach at Hogwarts. He had absolutely no doubt whatsoever that she was a competent educator: her ego would demand nothing less. But whether her students would be left unscathed at the end of it…well, that was another story. He would almost pity Lockhart. Almost.

* * *

Lockhart, while regaling McGonagall with a tale of one of his adventures (and not noticing, or deigning to do so, that her lips were rather thin and the smile rather fixed) suddenly sneezed. Unfamiliar as he was with the paradigm that, if someone was talking about him behind his back, he would sneeze, he instead inwardly panicked, and hoped he could talk Pomfrey into giving him a potion to prevent a cold.

He didn't know it, but colds were to be the least of his problems while teaching at Hogwarts…

 **CHAPTER 5 ANNOTATIONS:**

 **So, there you go. Malfoy's got another victim in mind, Dobby's tried blocking the barrier, and GLaDOS uses a sensible solution. Don't worry, Freeman got back to Aperture all right. But Lockhart is doomed. MWAHAHAHAHA!**

 **A few reviews from the previous chapter pointed out (not unreasonably) that Malfoy couldn't have slipped the Diary into Ginny's cauldron, not with GLaDOS watching him. Hence the bit at the beginning: Ginny hasn't been given the Diary this time.**

 **Review-answering time!** **Aust Sakura Kryzor** **: Actually, I wanted to ship Chell with Remus.**

 **Guest** **(regarding Wheatley sounding intelligent): Well, as the old saying goes, even broken clocks are right twice a day.**

 **Dustiniz117** **: No, they won't be. Except maybe in brief cameos.**

 **storyreader21** **: Glad you like it, but…well, I dunno about that. Maybe GLaDOS will take blood samples from her in the name of SCIENCE!, and do CAT scans (bad pun unintended), but I think Harry will persuade GLaDOS to let Hermione become a normal human again. Though I think GLaDOS may prank Hermione later on with something similar.**

 **frolovkrill7** **: No.**

 **1\. Explained in Douglas Adams' third** ** _Hitch-Hiker's Guide to the Galaxy_** **book,** ** _Life, the Universe and Everything_** **. Which, incidentally, was based on an unused** ** _Doctor Who_** **script by Adams,** ** _Doctor Who and the Krikkitmen_** **. No, really!**


	7. Chapter 6: Can This Travesty Really Be

**CHAPTER 6:**

 **CAN THIS TRAVESTY REALLY BE CALLED A TEACHER?**

The day had been going so well. As much as Harry didn't like the physical gardening aspects of Herbology, he still found the theory fascinating, even if the mandrakes were ugly as hell. Transfiguration was staying around the top of his favourite lessons. But then, after lunch, they had Defence Against the Dark Arts. Or, as Harry and Hermione would come to know it as, the Hyperbaric Ego Chamber.

On the one hand, you had Lockhart, whose self-aggrandizement was breathtaking, and not in a good way. It was breathtaking in the same way as Aperture-brand neurotoxin was. On the other, you had GLaDOS, a genius computer who wasn't afraid to voice her barbed opinions about everyone else's stupidity.

As they headed to class after lunch, Harry had to also deal with some kid with a camera by the name of Creevey, who seemed in awe of Harry (and so had Ron's little sister Ginny, of course). And while Harry did have something of an ego, he wasn't actually comfortable with the fame he had as the Boy Who Lived. Damn, he hated that appellation. He allowed for one photo…and then got jeered at by Malfoy.

"I don't think getting your head cut open makes you special, myself," Draco sneered, concluding his insults.

"Oh, it depend on what bit's cut out of it. Do you know what a leucotomy is, Malfoy(1)?" Harry said with his best passive-aggressive tone (his great-aunt would be proud). On Malfoy's confused headshake, Harry asked, "A frontal lobotomy? Huh. I thought you'd be familiar with the techniques, as your retainers seem to have undergone the magical equivalent. The same goes for Professor Lockhart. Ask Professor Snape what a lobotomy is, he should be able to tell you."

Hermione's lips twitched. "Why is the Mudblood trying not to laugh?!" Malfoy demanded, only to find Harry right in his face, his expression stormy.

In a too-calm, too-quiet voice, Harry said, "Use that word to describe Hermione again, Draco Malfoy…and I will volunteer you to great-aunt GLaDOS for practical lessons. I am trying to be nice, trying to be civil, but you throw it back in my face. You are the one refusing to be civil or nice, covering up your imbecilic bigotry which has the scientific basis of zilch, nada, nothing, with the threat of siccing your father on me. I'll be blunt, Draco Malfoy, your father does not scare me. I have faced scarier things than him. If you were serious about wanting to be friends with me, then you'll be civil to Hermione. Otherwise, _go away and stop bothering me_."

Before Draco could sneer back in bravado, Lockhart intervened from nearby…and promptly turned it into a double photo-op, before trying to offer Harry some advice about his fame. Harry tried hard not to gag.

Hermione, at least, was willing to give Lockhart the benefit of the doubt. While she did concede the points GLaDOS and Harry made about Lockhart's exploits, she also pointed out that they had plenty of useful information. Which was true. Which was why the proof of the pudding was in the eating.

As they entered the DADA classroom, Harry thought about last night. As predicted, Luna Lovegood went into Ravenclaw, and when she began to alienate some of the other Ravenclaws with her eccentric behaviour, Harry made it very clear, as did Hermione, that she was under their protection. Hermione had been with Luna and Ginny for the trip to Hogwarts, and had argued with the girl about the creatures she spoke of, though Ginny smoothed things over. And Hermione followed Harry's lead. This seemed to bridge things between the two witches, especially when Hermione learned about the fate of Luna's mother.

Marietta Edgecomb, however, had some choice words to say about Luna, and it was only Flitwick's appearance that stopped Harry from retaliating. Harry was disappointed in Marietta, as he thought they were friends, or at least on decent terms. Cho was better inclined towards Harry, though. It was more fair to say that Marietta was Harry's friend through Cho rather than anything else. Cho Chang opted to remain neutral about Luna.

His great-aunt was standing there, looking rather stony-faced as Harry and Hermione entered, while Lockhart beamed. As soon as everyone was seated, Lockhart held up Hermione's copy of _Travels with Trolls_ and held it up to show his portrait on the front. "Me," he began. "Gilderoy Lockhart, Order of Merlin, Third Class, Honorary Member of the Dark Force Defence League, and five times winner of _Witch Weekly_ 's Most Charming Smile Award. But I don't talk about that last one. After all, I didn't get rid of the Bandon banshee by merely smiling at her."

Nobody laughed. And Harry thought, _That joke physically hurt me_. GLaDOS' rolling eyes suggested that she shared the same opinion.

"Now, most of you will not be familiar with my glamorous assistant, very nearly as intelligent and beautiful as I am, though I must say, her repertoire of repartee exceeds even my own! Professor Gladys Johnson of Aperture from the United States of America!"

No applause, but GLaDOS certainly gained more attention now. " _Hello, and welcome to this enrichment session. Before we start, however, keep in mind that, although fun and learning are the primary goals of all DADA activities, serious injuries may occur. For your own safety, and the safety of others, please refrain from any activity that will lower your IQ, such as drinking alcoholic beverages, reading fanfiction, and casting magic. I am required to remind you that we are committed to the well-being of all participants. Cake, and grief counselling, will be available at the conclusion of the lessons. Thank you for helping us help you help us all(_ _2)_ _._ "

The silence that followed was so thick, you could spread it on bread. Hermione shot Harry a look of annoyance and fear mixed together. As much as she already knew of GLaDOS' dark sense of humour, this was beyond what she was used to.

Lockhart laughed a nervous laugh, and said, "Like I said, her sense of humour is very sophisticated. Just out of interest, will there actually be cake, Professor Johnson?"

" _I did not stutter, Professor Lockhart. The cake is_ _ **not**_ _a lie, contrary to popular opinion._ "

Lockhart nodded, before he rallied, and said, "Right! Well, I see everyone here has a complete set of my books. Thank you very much! Anyway, Professor Johnson and I thought we would start with a little quiz, but we had a mild…disagreement about what it should be about. So, we opted to use two separate quizzes. Professor Johnson, admittedly, hasn't done as comprehensive a quiz as mine, so you should be able to blaze through it like the proverbial hot knife through butter. And mine should not be anything to worry about, just something to see how well you've read them…"

* * *

Oh dear GLaDOS **_no_**. They had forty minutes to complete 54 questions on Lockhart's quiz, and 12 questions on GLaDOS'? Harry grimaced when he saw the types of questions on Lockhart's, too, so he began writing snarky answers to some of them, some in Latin and some in English. Everything sounded profound in Latin, unless it was the mangled Latin the wizards used for their spells.

For example, the answer to question 1 (Lockhart's favourite colour), he wrote down _livor mortis_. It literally meant 'bluish colour of death', and meant the discoloration that appeared on a corpse. Question 2 (about Lockhart's ambition), he put down, as a bit of snark, 'he has already achieved it: blinding the masses with his dazzling smile'. Question 3 was answered in the same way.

It went on in this vein, until he reached the last question, about Lockhart's birthday and his ideal gift. He wrote down the correct birthdate (he had, after all, read the books anyway, and found them moderately entertaining, and had answered the less ego-oriented ones that way), and put in, as some snark, a trepanation(3) as an emergency measure for self-image hypertrophy.

His great-aunt's test was considerably more challenging, and in a good way. She had asked, for example, a name of one of the Unforgivable Curses, the correct procedure when dealing with brief, acute Dementor exposure (chocolate, of all things, was a potent restorative after Dementor exposure! Thank you, Moony!), and to name a key skill of a Cursebreaker (Harry suspected GLaDOS put that one in for Ron to answer, given that his brother, Bill, was a Cursebreaker for Gringotts). He was smiling when he finished that one. It was challenging, and refreshingly so.

Unfortunately, it was spoiled when Lockhart collected the exam papers and marked them (well, his), and tutted. Harry knew the correct answers to most of them, he just didn't care enough to put most of the correct answers down. His great-aunt was right, the books were more glorified travelogues than DADA texts, and while they had useful information, the test questions were less about those and more about Lockhart's personal qualities…though calling them _qualities_ was something of a stretch.

GLaDOS, however, was even more scathing…though Harry was used to it. Her tongue was sharper than monofilament razor wire, even that experimental stuff Cave Johnson had created to dice lemons for burning, and which could cut through even diamond…

* * *

"… _And another thing, Mr Malfoy_ ," GLaDOS said. " _As Mr Goyle is your vat-cloned bodyguard, minion and retainer, I would like you to help instruct him on good penmanship, and the fact that fire, as much as I would like it to be, is not the solution to all problems. Neither is punching, despite what a certain Mr Duggan would believe(_ _4)_ _. Your own responses are certainly…adequate, but keep in mind I can read hundreds of different languages, including multiple variants of Latin, so be careful what you write down as insults in the margins. Please ask your Head of House what happened to a certain Mr Pettigrew if you think you can press your luck with your admittedly impressive command of Medieval Latin._ "

Draco paled, even as he tried to scowl. Harry would later learn that Snape had, indeed, warned the blonde ponce about annoying GLaDOS, with graphic details of what happened to Pettigrew. Harry was already blasé about the various dubious experiments at Aperture, but knowing Pettigrew's gruesome fate was very satisfying. A shame he wasn't there in person to see it happen.

With GLaDOS having finished her dressing down of Draco Malfoy, Lockhart beamed. "Now, now, my dear colleague, perhaps it's past time that we got down to the nitty-gritty of the subject matter?"

" _Well past time_ ," GLaDOS said dryly.

"Very well!" Lockhart proclaimed dramatically. "Now, be warned! It is our job to prepare you to face the foulest creatures known to wizardkind! You may find yourself facing your worst fears in this room…"

" _I doubt it, as you wouldn't let me bring in a Boggart_ ," GLaDOS snarked.

Lockhart actually shot a glare at GLaDOS, much to Harry's surprise. Either he really was stupid, or else…nah, he was just stupid. "Now, keep in mind that no lasting harm can befall you whilst we are here. All I ask of you all is to remain calm," he concluded, as he lifted a large cage from behind the desk. "And don't scream, as it may provoke them."

Harry would have been more anxious, had he not noted his great-aunt rolling her eyes in disdain. And soon, he realised why when Lockhart dramatically whipped off the cover from the cage, to reveal the caged creatures as Cornish Pixies.

Only one thought went through Harry's mind as he looked at the electric blue creatures flatly. _What_.

Okay, while they weren't particularly dangerous in of themselves, they were mischievous and tricky. Dealing with them might be a bit of a task for younger students, at least _en masse_. Then again, he was teaching a group of Ravenclaws and Slytherins, who had studied ahead. The former because it was learning, and the latter because they were ambitious enough to learn things ahead of time…especially relating to the Dark Arts.

And then, Lockhart showed himself to be even more like Wheatley than they suspected and opened the cage door, allowing the little critters to swarm out. Utter bedlam ensued. Harry watched with amusement as Malfoy was hauled by his ears by a pair of Pixies. A few tried to attack GLaDOS, only for them to be given a Look. Harry knew that Look: it was the Look of Uncertain Death.

As the Pixies broke things and vandalised most of the classroom, Lockhart looked confused. After admonishing them to try to stop them, he decided to try a spell of his own. " _Peskipiksi Pesternomi!_ " he yelled as he brandished his wand.

If there was such a spell (and Harry realised it was just a mangling of English instead of the mangled Latin wizards usually used: 'Pesky Pixie Pester No Me'), it had sod-all effect. Indeed, one of the Pixies took his wand, and threw it out of the window, causing Lockhart to dive under his desk. The chandelier, along with its burden of Draco Malfoy, crashed to the floor. GLaDOS sighed a long-suffering sigh, before she snapped her fingers. Suddenly, the Pixies all looked at her. She pointed to the cage. " _Go from Outside to Inside, or I will make your Insides go Outside._ "

A few went for the window, only for GLaDOS to fire a spell at them, causing them to drop, smoke purling from their bodies as they twitched. With a series of chittering shrieks, the others all flew into the cage. GLaDOS plucked the zapped Pixies off the floor, and none too gently tossed them back into the cage, before shutting it and locking it. As the bell rang, she remarked, all too smugly, " _Here endeth the lesson._ "

Harry knew that his great-aunt had most definitely left an impression. On the other students, on Lockhart, and on the Pixies. Harry couldn't help but notice an annoyed expression flash across Lockhart's face, before he recovered his equilibrium, and smiled. "Thank you, Professor Johnson. Well, that was most certainly a learning experience. Now, I expect those of you who didn't do very well on my pop quiz to revise my books. You never know when certain information may come in useful."

Harry met the eyes of his great-aunt, and knew he was sharing the same thought as her. Can this travesty of a man really be called a teacher? They both suspected, as they had for some time, that the answer was no…

 **CHAPTER 6 ANNOTATIONS:**

 **Okay, sorry for the long wait for a new chapter, and I'm afraid it'll still be a long wait for the new chapters anyway. Frankly, I suck at writing sequels to my stories now. I like fresh and new ideas to do, not continuations of stories I've finished. I'll try to continue the sequel stories I have published, including this one, but no promises.**

 **That being said, this chapter comes with a huge update for me. It includes the final chapter of one of my oldest fics, my** ** _Naruto_** **fic** ** _Observations of a Wannabe Kunoichi_** **, along with the first chapters of my 100** **th** **story, a** ** _Kingdom Hearts_** **crossover with the Potterverse called** ** _Hollow Heroes_** **.**

 **1\. As you might have inferred, a leucotomy is another name for a lobotomy, coming from 'leuco' or white, as it involves removing white matter from the brain…usually the frontal lobe.**

 **2\. If GLaDOS' speech sounds at all familiar, it's because it's a modified hybrid version of her speeches from Test Chamber 1 and Test Chamber 15 of the original game.**

 **3\. Yet another head surgery joke: trepanation is one of the oldest surgical procedures, by drilling a hole into the skull. In modern times, it's used to treat epidural and subdural haematomas, amongst other things.**

 **4\. Duggan was a rather…aggressive detective who teamed up with the Doctor and Romana in the excellent** ** _Doctor Who_** **story** ** _City of Death_** **. He had a bad habit of punching people…though this came in handy when he punched out the villain of the story in time to save humanity, leading the Doctor to say that it was the most important punch in history.**


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